Piston pump for delivering viscous pastes

ABSTRACT

A piston pump for delivering viscous fluids such as ink paste has an outlet valve in the form of a disc surrounding the pump piston rod and closing one end of the pump cylinder, the other end of the cylinder being open to form an inlet port when the piston projects beyond it at the end of the suction stroke. The outlet valve is closed by friction with the piston rod by a spring on the suction stroke and is opened by the pressure of fluid drawn into the cylinder on the working stroke. The valve and piston are quickly detachable from a drive mechanism comprising a motor and gearing which are suspended from a mounting movable vertically above a fluid container in which the pump is housed when working. The pump carries at its suction end a pressure plate which is a close sliding fit within the container wall or walls. Two or more pumps may be mounted on the same pressure plate.

United States Patent [1 1 Schnhmann et a1.

[54] PISTON PUMP FOR DELIVERING VISCOUS PASTES [75] inventors: SiegfriedSchuhmann; Hans Alix,

both of Offenback A.M., Germany [73] Assignee: RolandOffsetmaschinenfabrik Faber & Schleicher AG, Offenbach am Main, Germany[22] Filed: Nov. 9, 1970 [21] App]. No.: 87,866

[30] Foreign Application Priority Data Nov. 15, 1969 Germany ..P 19 57559.8

[52] US. Cl. ..417/360, 417/454, 417/487 [51] Int. Cl ..F04b 17/09,F04!) 21/00, F0413 39/10 [58] Field of Search ..417/489, 454, 360, 451,452; 222/385 [56] References Cited UNITED STATES PATENTS 593,885 11/1897Greer ..417/61 2,403,122 7/1946 Reisert et al.. .....222/385 X 2,409,96210/1946 Shearman ..417/489 X 2,420,151 5/1947 Renouf et a1. ..417/452 X[4 1 March 6, 1973 Campbell ..417/489 X Rotter ..417/489 X 5 7] ABSTRACTA piston pump for delivering viscous fluids such as ink paste has anoutlet valve in the form of a disc surrounding the pump piston rod andclosing one end of the pump cylinder, the other end of the cylinderbeing open to form an inlet port when the piston projects beyond it atthe end of the suctionstroke. The outlet valve is closed by frictionwith the piston rod by a spring on the suction stroke and is opened bythe pressure of fluid drawn into the cylinder on the working stroke. Thevalve and piston are quickly detachable from a drive mechanismcomprising a motor and gearing which are suspended from a mountingmovable vertically above a fluid container in which the pump is housedwhen working. The pump carries at its suction end a pressure plate whichis a close sliding fit within the container wall or walls. Two or morepumps may be mounted on the same pressure plate.

6 Claims, 9 Drawing Figures PISTON PUMP FOR DELIVERING VISCOUS PASTESThe invention relates to a single-acting piston pump for deliveringviscous fluids such as pastes from a storage container to a consumerstation, wherein the suction aperture of the pump is controlled by thedelivery piston.

It is the object of the invention to provide a pump which is suitable,in particular, for delivering viscous offset printing inks from an inkcontainer to the ink fountain of a printing press, and which is easy toservice and can be rapidly cleaned.

A plunger pump for delivering milk or the like is already known throughGerman Pat. specification No. 47578, wherein the pump housing and theplunger can be separated from one another and so the pump can be bettercleaned. The pump contains a ball valve at the pressure side and isunsuiable for the delivery of viscous pastes. The accessibility,particularly to the ball valve, necessary for cleaning, is inadequate.

In the present invention the pump outlet is controlled by an outletvalve which is guided on the piston rod and can be positively urged intothe closed position, and the piston rod extends through the cylindercover closing the cylinder pressure chamber, and outlet valve, deliverypiston and cylinder cover can be removed from the cylinder body. As aresult of this arrangement, particularly rapid and simple dismantlingand cleaning of the pump is possible. The dismantling is effected bymeans of a single manual operation. There are no dirt traps which needspecial cleaning, such as ball valves, in the arrangement according tothe invention.

Preferably there are provided a rapid locking device by means of whichthe piston pump can be connected precisely to a drive unit, and a quickrelease coupling by means of which the piston rod can be coupled to thedrive unit. This means is particularly advantageous when the parts ofthe pump soiled by the ink have to be cleaned individually, as may beadvisable, for example, on a change of ink.

The cylinder cover can be connected to the cylinder by means of abayonet locking device. This is a particularly rapid attachment which issimple to release.

In one form of the invention, the outlet valve is urged by a spring intothe closed position and by paste displaced by the piston during theworking stroke into the open position. An automatic valve of this kindis particularly simple and operationally reliable.

In another form of the invention, the outlet valve is urged into theclosed position by friction occurring between outlet valve and pistonrod during the suction of the piston, and into the open position by thepaste displaced by the piston during the working stroke. With thisarrangement, a spring is saved and so there is an advantage with regardto costs and maintenance. The provision of a helical spring inparticular could render cleaning of the pump more difficult.

In a specific embodiment of the invention, the delivery pump emergescompletely from the cylinder during the suction stroke. Thus there is aparticularly favorable cross-section available for the materal flowinginto the pump cylinder and this has a particularly favorable effect witha viscous offset printing ink.

In another embodiment of the invention, the piston comprises recessesextending in the axial direction of the piston at the circumference. Atthe end of the suction stroke, the piston only projects so far from thecylinder that the paste can flow into the interior of the cylinderthrough the recesses. The guiding of the piston in the cylinder isretained in this manner.

In another embodiment of the invention, the cylinder walls have slotsextending in the axial direction. The piston also remains guided in thecylinder in this manner.

Preferably, the suction side of the pump is connected to a pressureplate, the cross-section of which is such that it just fits into thestorage container. The pressure plate is preferably interchangeable inorder to adapt the delivery pump for use for storage containers ofdifferent shapes.

A pressure plate is equipped with two or more pumps. This arrangementleads to a particularly compact form of construction which is easy toservice and which can be used to particular advantage on perfectingpresses, wherein both sides of a web of paper are printed with the sameink but the ink consumption differs.

Some exemplifying embodiments of the invention are illustrateddiagrammatically in the accompanying drawings, in which:

FIG. I shows a piston pump according to the invention immersed in an inkcan, partially in section;

FIG. 2 shows a side view of the device shown in FIG.

FIG. 3 is an enlarged detail from FIG. 1, and shows the cylinder body ofthe pump according to one embodiment;

FIG. 4 shows the same details in FIG. 3 but seen from another direction;

FIG. 5 shows another embodiment of the delivery piston;

FIG. 6 shows a plan view of the piston shown in FIG. 5;

FIG. 7 shows a section through a specially constructed cylinder body ina further embodiment;

FIG. 8 shows a section on the line VIII-VIII in FIG. 7; and

FIG. 9 shows an elevational view of two piston pumps of the type shownin FIG. 1.

A piston pump 1 is connected to a drive unit, consisting of an electricmotor 3 and a gear 4, by means of a snap closure 2. The rapid-lockingdevice 2 consits of a quick adjusting screw 5 and fitting pins 6,7. Thegear 4 is a crank gear which converts the rotary motion of the electricmotor 3 into a reciprocating motion of a connecting rod 8. Theconnecting rod 8 can be connected to a piston rod 10 of the piston pump1 by means of a quick-release coupling 9. As shown in FIG. 4, thequick-release coupling 9 consists of a pin 11 which is secured againstfalling out by means of a resilient safety plate 12. The piston rod 10is reciprocated in a cylinder 13. An outlet valve 14 is constructed inthe form of an annular disc and is guided on the piston rod 10 with theinterposition of a seal 15. During the downward movement of the pistonrod 10, the valve 14 is restrained by friction and urged against a valveseat 16. For this it is necessary for the piston stroke h to be greaterthan the distance v covered by the valve 14. When the piston 17 emergesfrom the cylinder 13 the position shown in FIGS. 3 and 4 in broken linesthe pasty but flowable material to be pumped flows into the cylinder 13.During the upward movement of the piston 17, the outlet valve 14 isautomatically urged away and the material is pumped into a pressure line18 leading to a consumer station or point of utilization (see FIG. 1).

The storage container to be pumped empty, here an ink can 19, is placedon the lower plate 20 of a frame 21. A pressure plate 23 is secured to aflange 22 mounted at the suction side of the pump 1. The pressure plate23 just fits into the ink can 19 with the interposition of a sealingring 24 so that the whole unit consisting of pump 1, gear 4 and motor-3inserted into the ink can 19 is gradually lowered as the ink leveldrops, the wall of the can being scraped clean of ink by the sealingring 24. The vent valve 25 facilitates removal of the unit 1, 3, 4. Theunit consisting of gear 4,motor 3 and pump 1 is connected to a crossbar26 at each end of which there is mounted a pair of rollers 27, 28 and29, 30. One roller 28, 30 of each pair of rollers is mounted directly atan end 31, 32 respectively of the crossbar 26, while the other roller27, 29 of each pair of rollers is mounted on an arm 33, 34 secured tothe crossbar 26. Each pair of rollers is guided in a groovelike guideprovided in a longitudinal bar 35 36 of the stand. The entirearrangement can be suspended from a hook 38 mounted on a furthercrossbar 37 of the stand. In this suspended position, the pump 1 can bedisconnected from the gear 4 by releasing the quickrelease coupling 9and the rapid-locking device 2.

The piston rod is guided by the cylinder cover 39 and sealed off fromthe cylinder compartment by a seal 40. The cylinder cover 39 is securedto the cylinder body 41 by means of a known bayonet locking device whichcan be rapidly released. A pin 42 which is secured to the cylinder body41 is inserted into a longitudinal groove 43 provided in the cover 39when the cylinder cover 39 is placed in position and enters an annulargroove 44 provided in the cover 39 when the cover 39 is turned (F168. 3and 4). A further resilient seal 45 is mounted between the cylinder body41 and the cover 39 (FIGS. 3 and 4).

FIGS. 5 and 6 show another embodiment of the piston 17 of the pistonpump 1. The piston 17 comprises, at its circumference, recesses 46through which the material to be pumped can pass when the piston 17 hastravelled partially out of the cylinder 13. As a result, the piston 17remains constantly guided in the cylinder 13 by webs 47. The outletvalve 14 is here urged against the valve seat 16 by a spring 48.

FIGS. 7 and 8 show a further embodiment of a cylinder 13 of the pistonpump 1. The cylinder 13 comprises slots 49 at its circumference so thatthe material to be pumped can enter even when the piston 17 has not beendriven out of the cylinder 13. Here, too, constant guiding of the pistonis obtained by raised portions 50.

Finally, FIG. 9 shows two pumps and the components associated therewithmounted on pressure plate 23.The reference numerals applied to thesecond pump are the same as used for the first pump but primed. Bothpumps serve to pump the material out of supply can 19.

What is claimed'is:

l. A pumping device for pumping viscous fluid from a storage containerto a point of utilization, said pumping device comprising incombination:

an open storage container for the fluid to be pumped;

a cylinder having at one end a detachable cover and being open at theother end, said open end being disposed to extend into the storagecontainer and constituting the intake side of the pumping device;

a piston slidable in the cylinder between a lower limit position and anupper limit position;

a piston rod mounting said piston and slidably extended through thecover of the cylinder;

drivemeans coupled to the piston rod for imparting to the same and thusto the piston a reciprocating movement;

conduit connected to the cylinder for delivering fluid to the point ofutilization;

a valve means for opening and closing the connection between thecylinder and the conduit, said valve means being controlled by the upand down movements of the piston so as to close said connection by thedownward movement of the piston and to open said connection by theupward movement of the piston;

a quick-release fastening means releasably securing the cover to thecylinder for quick withdrawal of the cover, the piston rod with thepiston thereon and the valve means from the cylinder upon release ofsaid fastening means;

a quick-release fastening means releasably securing the piston rod tothe drive means; and

quick-release fastening means releasably securing the cylinder to thedrive means.

2. A pumping device for pumping viscous fluid from a storage containerto a point of utilization, said pumping device comprising incombination:

an open storage container for the fluid to be pumped;

a cylinder having at one end a detachable cover and being open at theother end, said open end being disposed to extend into the storagecontainer and constituting the intake side of the pumping device;

a piston slidable in the cylinder between a lower limit position and anupper limit position;

a piston rod mounting said piston and slidably extended through thecover of the cylinder;

drive means coupled to the piston rod for imparting to the same and thusto the piston a reciprocating movement; I

a conduit connected to the cylinder for delivering fluid to the point ofutilization;

a valve means for opening and closing the connection between thecylinder and the conduit, said valve means being controlled by the upand down movements of the piston so as to close said connection by thedownward movement of the piston and to open said connection by theupward movement of the piston;

said valve means including a valve seat formed within the cylinderintermediate the length thereof and a valve disc slidably seated on thepiston rod with a friction fit, movement of the piston toward its lowerlimit position causing said disc to be moved into sealing engagementwith said seat thereby closing the valve means but permitting furtherdownward movement of the piston, said closing of the valve 'meansinterrupting the connection between the cylinder and the conduit, upwardmovement of the piston toward its upper limit position lifting the discclear of the valve seat thereby opening the valve means; and

3 ,7 1 9 ,43 7 5 6 a quick-release fastening means releasably securing4. The pumping device according to claim 1 wherein the cover to thecylinder fo qui k th a of said quick-release fastening means comprises abayonet the cover, the piston rod with the piston thereon lock means onthe cylinder and the cover.

and the Valve means from the cylinder upon 5. The pumping deviceaccording to claim 1 wherein release of sfiid fasfiening 5 said pistonhas in its circumference at least one recess 3. The pumping deviceaccording to claim 1 wherein extending through the thickness f thepiston plston m Its lower 1mm PPSmOn 18 below the.open 6. The pumpingdevice according to claim 1 wherein cylinder end thereby uncovering thecylinder for influx the cylinder has within the range of the pistonmoveof fluid from the container into the cylinder, movement of thepiston toward its upper limit position and thus 10 g at least one anallyelongate recess m Inner opening of the valve means delivering fluidwithin the w cylinder space above the piston to said conduit.

1. A pumping device for pumping viscous fluid from a storage containerto a point of utilization, said pumping device comprising incombination: an open storage container for the fluid to be pumped; acylinder having at one end a detachable cover and being open at theother end, said open end being disposed to extend into the storagecontainer and constituting the intake side of the pumping device; apiston slidable in the cylinder between a lower limit position and anupper limit position; a piston rod mounting said piston and slidablyextended through the cover of the cylinder; drive means coupled to thepiston rod for imparting to the same and thus to the piston areciprocating movement; a conduit connected to the cylinder fordelivering fluid to the point of utilization; a valve means for openingand closing the connection between the cylinder and the conduit, saidvalve means being controlled by the up and down movements of the pistonso as to close said connection by the downward movement of the pistonand to open said connection by the upward movement of the piston; aquick-release fastening means releasably securing the cover to thecylinder for quick withdrawal of the cover, the piston rod with thepiston thereon and the valve means from the cylinder upon release ofsaid fastening means; a quick-release fastening means releasablysecuring the piston rod to the drive means; and quick-release fasteningmeans releasably securing the cylinder to the drive means.
 1. A pumpingdevice for pumping viscous fluid from a storage container to a point ofutilization, said pumping device comprising in combination: an openstorage container for the fluid to be pumped; a cylinder having at oneend a detachable cover and being open at the other end, said open endbeing disposed to extend into the storage container and constituting theintake side of the pumping device; a piston slidable in the cylinderbetween a lower limit position and an upper limit position; a piston rodmounting said piston and slidably extended through the cover of thecylinder; drive means coupled to the piston rod for imparting to thesame and thus to the piston a reciprocating movement; a conduitconnected to the cylinder for delivering fluid to the point ofutilization; a valve means for opening and closing the connectionbetween the cylinder and the conduit, said valve means being controlledby the up and down movements of the piston so as to close saidconnection by the downward movement of the piston and to open saidconnection by the upward movement of the piston; a quick-releasefastening means releasably securing the cover to the cylinder for quickwithdrawal of the cover, the piston rod with the piston thereon and thevalve means from the cylinder upon release of said fastening means; aquick-release fastening means releasably securing the piston rod to thedrive means; and quick-release fastening means releasably securing thecylinder to the drive means.
 2. A pumping device for pumping viscousfluid from a storage container to a point of utilization, said pumpingdevice comprising in combination: an open storage container for thefluid to be pumped; a cylinder having at one end a detachable cover andbeing open at the other end, said open end being disposed to extend intothe storage container and constituting the intake side of the pumpingdevice; a piston slidable in the cylinder between a lower limit positionand an upper limit position; a piston rod mounting said piston andslidably extended through the cover of the cylinder; drive means coupledto the piston rod for imparting to the same and thus to the piston areciprocating movement; a conduit connected to the cylinder fordelivering fluid to the point of utilization; a valve means for openingand closing the connection between the cylinder and the conduit, saidvalve means being controlled by the up and down movements of the pistonso as to close said connection by the downward movement of the pistonand to open said connection by the upward movement of the piston; saidvalve means including a valve seat formed within the cylinderintermediate the length thereof and a valve disc slidably seated on thepiston rod with a friction fit, movement of the piston toward its lowerlimit position causing said disc to be moved into sealing engagementwith said seat thereby closing the valve means but permitting furtherdownward movement of the piston, said closing of the valve meansinterrupting the connection between the cylinder and the conduit, upwardmovement of the piston toward its upper limit position lifting the discclear of the valve seat thereby opening the valve means; and aquick-release fastening means releasably securing the cover to thecylinder for quick withdrawal of the cover, the piston rod with thepiston thereon and the valve means from the cylinder upon release ofsaid fastening means.
 3. The pumping device according to claim 1 whereinthe piston in its lower limit position is below the open cylinder endthereby uncovering the cylinder for influx of fluid from the containerinto the cylinder, movement of the piston toward its upper limitposition and thus opening of the valve means delivering fluid within thecylinder space above the piston to said conduit.
 4. The pumping deviceaccording to claim 1 wherein said quick-release fastening meanscomprises a bayonet lock means on the cylinder and the cover.
 5. Thepumping device according to claim 1 wherein said piston has in itscircumference at least one recess extending through the thickness of thepiston.